A backlight assembly includes a receiving container, a first side mold, a printed circuit board and a plurality of lamps. The first side mold is on the side of the receiving container. The printed circuit board is combined with the first side mold, the printed circuit board including a plurality of conductive clips and a power supply line assembly for transmitting a lamp driving electric power. The lamps are combined with the conductive clips to generate light based on the lamp driving electric power. The power supply line assembly includes a first conductive line electrically connected to a subgroup of conductive clips and a second conductive line electrically connected to the other conductive clips. The first and second conductive lines are supplied with the lamp driving electric powers that have reverse phases to each other. Therefore, noise is decreased according to its waterfall curve to improve an image display quality.